3-2 way expansion valve

ABSTRACT

A valve ( 1 ) is introduced for a heat pump system in a motor vehicle, with at least one inlet ( 3 ), at least two outlets ( 2, 4 ) and a valve element ( 7 ) which comprises at least one throughlet ( 8 ) and at least one expansion recess ( 9 ) that can be brought into fluidic connection with at least one outlet ( 2, 4 ).

FIELD OF TECHNOLOGY

The invention relates to a valve for a heat pump system in a motorvehicle.

PRIOR ART

As is the case for many other interior spaces, the demand for theinterior space of a motor vehicle is that it be air-conditioned to makeit comfortable for its passengers. In this regard DE 197 47 548 A1discloses a heating device for use in a motor vehicle and DE 192 53 357A1 discloses a combined cooling system/heat pump for operation in motorvehicles. A generally utilizable flow control valve is disclosed in U.S.Pat. No. 5,524,863. While it is known for an air-conditioning system toprovide a thermostatic expansion valve for the expansion of therefrigerant, there are additional requirements in heat pump systems.

DESCRIPTION OF THE INVENTION

Against this background the objective of the invention is to provide acost-effective and/or space-saving valve for a heat pump system.

This objective is attained through the valve described in patent claim1. Accordingly, this valve comprises at least one inlet and at least twooutlets as well as a valve element, in particular a single valve elementthat comprises at least one throughlet and at least one expansion recesswhich can be brought into fluidic connection with an outlet. Therebythat at least two outlets are provided, the refrigerant can be conductedin at least two directions which in efficient manner fulfills thefunctionality required for a heat pump. Moreover, according to theinvention advantageously on the valve element at least one expansionrecess, in particular an expansion slot is additionally provided, whichcan be brought into fluidic connection with one outlet, in two differentpositions advantageously with different outlets, such that therefrigerant is expandable into two different directions and,corresponding to the heat pump system, heating as well as alsoair-conditioning is feasible. The heating capacity is therewithimproved. The valve according to the invention, which can be denoted as3/2-way expansion valve, is of low complexity, fully fulfills therequirements and requires only small installation space. The throughletcan be referred to as “fully open” since the throughlet cross sectioncorresponds approximately to that of the at least one inlet or outlet orthe throughlet cross section is in any case markedly greater than thatof the expansion recess.

Preferred further developments of the valve according to the inventionare described in the further claims.

The valve according to the invention can advantageously comprise aclosure position in which there is no fluidic connection between theinlet and any outlet such that a separate cutoff valve can be omittedsaving cost and space.

An especially efficient utilization of the installation space isanticipated for that embodiment in which the completely openedthroughlet describes an angle of substantially 90 degrees.

As already indicated, the expansion recess can advantageously be anexpansion slot. Stated differently it can be a groove with preferablyU-shaped cross section whose depth, starting from its docking to thethroughlet cross section, preferably gradually decreases.

According to initial considerations advantageous properties of the valveaccording to the invention are expected especially when the valveelement is a sphere. However, cylindrical implementation as well asthose in the shape of a truncated cone are also feasible.

The form of the valve element is especially simply for that preferredimplementation in which two outlets are essentially aligned with oneanother such that, by means of a rotation of the valve element aboutsubstantially 180° starting from a fluidic connection with the oneoutlet, the inlet can be brought into fluidic connection with the otheroutlet.

For a simple structure of the valve according to the invention it hasfurther been found to be advantageous if a valve shaft connected withthe valve element is essentially in alignment with the inlet.

BRIEF DESCRIPTION OF THE FIGURES

In the following an embodiment example of the invention depicted in thedrawing will be explained in detail. Therein depict:

FIG. 1 a schematic representation of the valve according to theinvention in a first position;

FIG. 2 a schematic representation of the valve according to theinvention in a second position;

FIG. 3 a schematic representation of an embodiment of the valve element.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

As is evident in FIG. 1, a valve element 7, in the depicted embodimenthaving the shape of a sphere, is actuatable by means of a valve shaft 6through a rotary drive 1, which typically can be implemented as electricactuator or electric control element. The valve element 7 is received ina valve block 5 that comprises an inlet 3 and two outlets 2, 4. Itshould be stated that the outlets 2, 4 can also be used as an inlet andthe inlet 3 can also be used as an outlet.

As is evident in FIG. 1, in the valve element 7 an angled, substantiallyL-shaped throughlet 8 is provided, whose cross section correspondssubstantially to that of inlet 3 and/or outlet 2, 4. In the positionshown in FIG. 1, consequently, a largely unimpeded throughflow of therefrigerant is possible. This applies equally to a position, not shownin the Figures, in which the valve element is rotated by 180° by meansof the valve shaft 6 about a vertical axis, according to the Figures,such that the throughlet 8 is substantially directed toward the outlet4.

In contrast, in FIG. 2 a position is indicated in which the valveelement 7, compared to the position shown in FIG. 1, has been rotatedcounterclockwise from a top view by 90°, in the direction of the viewer.The indicated expansion recess 9 comes into fluidic connection with theoutlet 2, while the aperture, pointing according to the position of FIG.1 to the outlet 2, of the valve element 7 is directed toward the viewerof FIG. 2, and is here in contact on an inner wall of the valve block 5such that it is blocked. Accordingly, the refrigerant flowing in throughthe inlet 3 can only flow out through the expansion recess 9 and hereinis expanded.

This applies equally, and advantageously suitably, to a heat pumpsystem, in the direction of the other outlet 4 in that position whichresults from the position shown in FIG. 2 thereby that the valve element7 is rotated about its axis by 180°. In this position the expansionrecess 9 is in fluidic connection on the side facing away from theviewer of FIG. 2 with the outlet 4 and enables the expansion of therefrigerant in this direction.

In FIG. 3 is depicted a practical embodiment of the, in this case,spherical valve element 7. The openings to the throughlet 8 in theexample shown are substantially circular and the openings, essentiallymeeting in the center of the sphere, can be implemented by drilling. Theexpansion recess 9 is connected to one of the openings at its aperturewhich can be brought into fluidic connection with one of outlets 2, 4and, at the site of the docking to the aperture, has a depth of a fewmillimeters. The cross section of the groove forming the expansionrecess 9 is substantially rectangularly U-shaped, however it can also beV-shaped, rounded or formed in any other way.

The expansion recess 9 extends substantially in the plane which includesthe axis of aperture 10 to which it is docked and approximately over aquarter circle along the circumference of the sphere. Its depthdecreases continuously herein. Arrows A indicate that the refrigerantinitially flows in the interior of the sphere according to FIG. 3essentially in the vertical direction and subsequently laterally throughthe expansion element 9 toward the outside. In the depicted case theexpansion recess 9 is consequently developed along the “equator” of thesphere from which also one of apertures 10 extends, while the apertureof the inlet 3 is implemented at a “pole”. In particular when theexpansion recess 9 extends less far along the circumference of thesphere, a completely closed position is possible thereby that thesphere, starting from the position shown in FIG. 2, is rotated towardthe right until there is no longer a fluidic connection from theexpansion recess 9 to the outlet 2 and aperture 10 has not yet come intofluidic connection with the outlet 4.

1. A valve for a heat pump system in a motor vehicle, with at least oneinlet, at least two outlets and one valve element comprising at leastone throughlet and at least one expansion recess that can be broughtinto fluidic connection with at least one outlet.
 2. A valve accordingto claim 1, further comprising a shutoff position.
 3. A valve accordingto claim 1, wherein the completely open throughlet comprises an angle ofsubstantially 90°.
 4. A valve according to claim 1, wherein at least oneexpansion recess is a slot.
 5. A valve according to claim 1, wherein tthe valve element is substantially sphere-shaped.
 6. A valve accordingto claim 1, wherein two outlets are substantially aligned with oneanother.
 7. A valve according to claim 1, wherein one inlet essentiallyaligns with a valve shaft connected with the valve element.
 8. A valveas in claim 2, wherein the completely open throughlet comprises an angleof substantially 90°.
 9. A valve according to claim 2, wherein at leastone expansion recess is a slot.
 10. A valve according to claim 3,wherein at least one expansion recess is a slot.
 11. A valve accordingto claim 2, wherein the valve element is substantially sphere-shaped.12. A valve according to claim 3, wherein the valve element issubstantially sphere-shaped.
 13. A valve according to claim 4, whereinthe valve element is substantially sphere-shaped.
 14. A valve accordingto claim 3, wherein the valve element is substantially sphere-shaped.15. A valve according to claim 9, wherein the valve element issubstantially sphere-shaped.
 16. A valve according to claim 2, whereintwo outlets are substantially aligned with one another.
 17. A valveaccording to claim 3, wherein two outlets are substantially aligned withone another.
 18. A valve according to claim 4, wherein two outlets aresubstantially aligned with one another.
 19. A valve according to claim5, wherein two outlets are substantially aligned with one another.
 20. Avalve according to claim 2, wherein one inlet essentially aligns with avalve shaft connected with the valve element.